Hearing loss loci segregating in consanguineous families from India and Pakistan were ascertained. Each family consisted of at least three affected children related to each other through at least one consanguineous union. Some of these families mapped to known loci such as DFNB3, DFNB4, DFNB6, DFNB7/DFNB9, DFNB8/DFNB10 and DFNB12. Others represent mutations in new DFNB genes that are being mapped. The new locus DFNB29 (found at 21q22) was mapped this past year in two large consanguineous families from Pakistan and the responsible gene was cloned. This manuscript is in preparation. An oral presentation of this work will be given during the upcoming meeting of the American Society of Human Genetics in early October (abstract 18, Molecular Basis of Mendelian Disorders I, session 14). Much progress has been made on the DFNB26 locus on chromosome 4q31. A manuscript is in preparation describing this interesting locus which has a mapped modifier locus on chromosome 1q23. The dominant modifier, DFNM1, protects family members from DFNB26 hearing impairment. An oral presentation of this work will be given during the upcoming meeting of the American Society of Human Genetics (abstract 56, Linkage mapping and polymorphisms I, session 18). Genome-wide scans are being performed on many consanguineous families that are not linked to known deafness causing loci.